Custom head gaskets sound pricey as well. Are OEM head gaskets really that bad? Is this not a closed deck engine?

You could do the PnP yourself if you learned how, keep the cost way down.
Custom head gaskets aren't as expensive as you think. My gaskets were about 90 a gasket & they were 3 layered MLS with a thick piece in the middle.
22Es are not closed deck engines but as monkeyposeur said, that does not matter. The pistons will be a problem long before the block is ever damaged.